Many of todays bottled liquid products give off harmful vapours which must be trapped within the bottle or container. Typical closure caps are made with interior liners of a material such as cardboard, cork, paper, and even metallic foil that is secured to the cap by means of a suitable adhesive.
None of the presently available liner securing adhesives are capable of withstanding the deteriorating action of solvent vapours. Furthermore, where these caps are used to seal a solvent container the actual liners themselves will break down and allow vapour escape from the containers.